[ Ref. "Seek Pressure & Vacuum Pump Units for Calliope", by
 [ Gene Calman, in 141216 MMDigest.  -- Robbie

These instruments were built some years ago.  There were no plans;
Mike Kitner had the design in his head and, basically, he built the
blower boxes to fit the motor units.  We built one for him and one for
me together.

The motor units were purchased from Grainger Industrial Supply.
The brand was Ametek.  They both were vacuum motors, one a standard
through-flow vacuum (Ametek #116432-00, Grainger stock #2M422) and
the other a tangential discharge vacuum motor with captured exhaust to
produce the wind supply (Ametek #116765-00, Grainger stock #4M922).

An AC dimmer switch is used as a means to control the vacuum motor
speed to adjust the vacuum level to about 25 inches water gage suction.
You have one level when just the vacuum motor runs and when you turn
on the one for pressure, the vacuum level drops down due to change in
air pressure inside the box.  You need a vacuum gauge showing vacuum
measured in inches of water column so you can adjust the vacuum level
with the machine playing.  They work okay but there are two problems
with doing it this way which I didn't foresee.

The first problem was that putting both turbine motors in one box
produced a wind supply wherein the air produced is very warm due to the
operating temperatures of the motors and the air passing through them.
In the Tangley, this excess air is exhausted by the spill valve right
alongside of the stack valves.

I take the back off the machine so the hot air can escape the cabinet.
With the back on the hot air is trapped in the cabinet and I worry
about the effect of the heat on the temperature sensitive glue in the
stack and other parts.

The temperature of the wind produced was running over 100 degrees F.
I modified the case on the vacuum/blower box with a fan to create air
flow through the box and this dropped the temperature to the 95 degree
area -- still too hot for my liking.  If I was making it again, I'd
design the box so both motors were not in the same box or at least in
two separated chambers in the same box.

The other problem is that two vacuum motors running the same time is
noisy.  Sounds like two vacuum cleaners running, which it really is.
With a Tangley the noise is a minor problem because the machine is so
loud.

The pictures and construction of the box may be seen on the
Carousels.com web site articles.  Click on the calliope restoration
project and then click on part 23.

Bill Black
Chambersburg, Pennsylvania

 [ http://www.carousels.com/bblack/calliope.php 
 [   Tangley Calliope Restoration Project (The Entire Series)
 [ http://www.carousels.com/bblack/calpt23.htm 
 [   The Vacuum And Pressure Supply (part 23)
 [ -- Robbie